Since prostaglandin (hereinafter referred to as PG) shows various important physiological actions in a trace amount, natural PG analogues and a vast number of derivatives thereof have been studied on synthesis and biological activities, with attempt to apply these compounds to pharmaceuticals. The results of the investigations are reported in a number of literature, Japanese Patent Application Kokai (Laid-Open) No. 100446/1977 (U.S. Pat. No. 4,029,681) , Japanese Patent Application Kohyo No. 502009/1990 (WO89/00559), etc. Among these publications, Japanese Patent Application Kohyo No. 502009/1990 discloses a group of PG derivatives which are substituted with a halogen at the 9-position; however, the physiological activities of these PG derivatives are not fully satisfactory.
The object of the present invention is to provide novel PG derivatives having strong ameliorating actions for renal failure, ischemic heart disease and heart failure.